Boolean Operations

For anyone who uses the internet, Boolean operations are part of our everyday existence: they are, by default, at work in all of your searches. And because they are latent and not manifest and you don’t know you are using them, the search engines are using them in a way that gives you the most results for your search, leaving the sorting and evaluating of results to you. In most cases, that means you scan through pages of search results in search of results worth your time, OR, you only look at the first one or two pages of not-very-useful results and reinforce the business plans of hundreds of businesses built around expiating search engine results. (The made search engine optimization an acronym [SEO] for a reason: it’s done so often.)

But what if Boolean operators were more easily understood? Andy Finnell wrote about Boolean operators in terms of graphics, but his graphical illustrators actually make Boolean operations more understandable to a larger audience.

*Note: I have reproduced Finnell’s table here, and re-used his graphics, so as not to add undue traffic to his website. The graphics below are his originals. I hope in time to expand this post a bit and to re-do the graphics to make them more in keeping with gray-ness of this site.*


Union (logical “or”)
Intersection (logical “and”)
Join (Exclusive “or”: written “EOR”)